The present invention relates to quick connect tube couplings. More particularly, the invention relates to a quick connect tube coupling that utilizes fewer seals and is easier to manufacture.
Quick connect tube couplings are well known in the art. One type of quick connect tube coupling that has found substantial commercial success is disclosed in U.S. Pat. No. 4,378,028, the entire disclosure of which is fully incorporated herein by reference. The present invention is directed to improvements in the coupling described therein to reduce the number of seals and sealing surfaces, thereby simplifying manufacturing processes and reducing costs without any compromise in performance of the coupling.
In accordance with one aspect of the invention, a quick connect coupling includes a valve seat member that has only two seals for providing a body seal against fluid pressure. In one embodiment, the valve seat member includes an outer surface with a seal groove therein and an inner surface with a seal groove therein. The seals are radially compressed within these seal grooves. Reducing the number of seals and seal surfaces simplifies manufacturing and thereby lowers cost.
In accordance with another aspect of the invention, a valve seat member is provided that seals against fluid pressure in such a way that a body extension of the female coupling component is not a wetted part. In one embodiment, an inner seal seals against an outer surface of a tubular stem portion of the male coupling member, and an outer seal seals against an inner surface of the female coupling body.